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[209.132.180.67]) by mx.google.com with ESMTP id x22-v6si2332874pfh.84.2018.08.17.10.28.27; Fri, 17 Aug 2018 10:28:43 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727882AbeHQUbf (ORCPT + 99 others); Fri, 17 Aug 2018 16:31:35 -0400 Received: from vps-vb.mhejs.net ([37.28.154.113]:46292 "EHLO vps-vb.mhejs.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727160AbeHQUbe (ORCPT ); Fri, 17 Aug 2018 16:31:34 -0400 Received: by vps-vb.mhejs.net with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1fqiWs-0007gP-CX; Fri, 17 Aug 2018 19:27:18 +0200 Subject: Re: [PATCH] block, bfq: return nbytes and not zero from struct cftype .write() method To: Jens Axboe Cc: Paolo Valente , linux-block@vger.kernel.org, linux-kernel , Arianna Avanzini References: <19c68f93-017d-cda1-632f-039ca3ca0158@kernel.dk> From: "Maciej S. Szmigiero" Openpgp: preference=signencrypt Autocrypt: addr=mail@maciej.szmigiero.name; prefer-encrypt=mutual; keydata= xsFNBFpGusUBEADXUMM2t7y9sHhI79+2QUnDdpauIBjZDukPZArwD+sDlx5P+jxaZ13XjUQc 6oJdk+jpvKiyzlbKqlDtw/Y2Ob24tg1g/zvkHn8AVUwX+ZWWewSZ0vcwp7u/LvA+w2nJbIL1 N0/QUUdmxfkWTHhNqgkNX5hEmYqhwUPozFR0zblfD/6+XFR7VM9yT0fZPLqYLNOmGfqAXlxY m8nWmi+lxkd/PYqQQwOq6GQwxjRFEvSc09m/YPYo9hxh7a6s8hAP88YOf2PD8oBB1r5E7KGb Fv10Qss4CU/3zaiyRTExWwOJnTQdzSbtnM3S8/ZO/sL0FY/b4VLtlZzERAraxHdnPn8GgxYk oPtAqoyf52RkCabL9dsXPWYQjkwG8WEUPScHDy8Uoo6imQujshG23A99iPuXcWc/5ld9mIo/ Ee7kN50MOXwS4vCJSv0cMkVhh77CmGUv5++E/rPcbXPLTPeRVy6SHgdDhIj7elmx2Lgo0cyh uyxyBKSuzPvb61nh5EKAGL7kPqflNw7LJkInzHqKHDNu57rVuCHEx4yxcKNB4pdE2SgyPxs9 9W7Cz0q2Hd7Yu8GOXvMfQfrBiEV4q4PzidUtV6sLqVq0RMK7LEi0RiZpthwxz0IUFwRw2KS/ 9Kgs9LmOXYimodrV0pMxpVqcyTepmDSoWzyXNP2NL1+GuQtaTQARAQABzTBNYWNpZWogUy4g U3ptaWdpZXJvIDxtYWlsQG1hY2llai5zem1pZ2llcm8ubmFtZT7CwZQEEwEIAD4WIQRyeg1N 257Z9gOb7O+Ef143kM4JdwUCWka6xQIbAwUJA8JnAAULCQgHAgYVCgkICwIEFgIDAQIeAQIX gAAKCRCEf143kM4Jdx4+EACwi1bXraGxNwgFj+KI8T0Xar3fYdaOF7bb7cAHllBCPQkutjnx 8SkYxqGvSNbBhGtpL1TqAYLB1Jr+ElB8qWEV6bJrffbRmsiBPORAxMfu8FF+kVqCYZs3nbku XNzmzp6R/eii40S+XySiscmpsrVQvz7I+xIIYdC0OTUu0Vl3IHf718GBYSD+TodCazEdN96k p9uD9kWNCU1vnL7FzhqClhPYLjPCkotrWM4gBNDbRiEHv1zMXb0/jVIR/wcDIUv6SLhzDIQn Lhre8LyKwid+WQxq7ZF0H+0VnPf5q56990cEBeB4xSyI+tr47uNP2K1kmW1FPd5q6XlIlvh2 WxsG6RNphbo8lIE6sd7NWSY3wXu4/R1AGdn2mnXKMp2O9039ewY6IhoeodCKN39ZR9LNld2w Dp0MU39LukPZKkVtbMEOEi0R1LXQAY0TQO//0IlAehfbkkYv6IAuNDd/exnj59GtwRfsXaVR Nw7XR/8bCvwU4svyRqI4luSuEiXvM9rwDAXbRKmu+Pk5h+1AOV+KjKPWCkBEHaASOxuApouQ aPZw6HDJ3fdFmN+m+vNcRPzST30QxGrXlS5GgY6CJ10W9gt/IJrFGoGxGxYjj4WzO97Rg6Mq WMa7wMPPNcnX5Nc/b8HW67Jhs3trj0szq6FKhqBsACktOU4g/ksV8eEtnM7AzQRaRrwiAQwA xnVmJqeP9VUTISps+WbyYFYlMFfIurl7tzK74bc67KUBp+PHuDP9p4ZcJUGC3UZJP85/GlUV dE1NairYWEJQUB7bpogTuzMI825QXIB9z842HwWfP2RW5eDtJMeujzJeFaUpmeTG9snzaYxY N3r0TDKj5dZwSIThIMQpsmhH2zylkT0jH7kBPxb8IkCQ1c6wgKITwoHFjTIO0B75U7bBNSDp XUaUDvd6T3xd1Fz57ujAvKHrZfWtaNSGwLmUYQAcFvrKDGPB5Z3ggkiTtkmW3OCQbnIxGJJw /+HefYhB5/kCcpKUQ2RYcYgCZ0/WcES1xU5dnNe4i0a5gsOFSOYCpNCfTHttVxKxZZTQ/rxj XwTuToXmTI4Nehn96t25DHZ0t9L9UEJ0yxH2y8Av4rtf75K2yAXFZa8dHnQgCkyjA/gs0ujG wD+Gs7dYQxP4i+rLhwBWD3mawJxLxY0vGwkG7k7npqanlsWlATHpOdqBMUiAR22hs02FikAo iXNgWTy7ABEBAAHCwXwEGAEIACYWIQRyeg1N257Z9gOb7O+Ef143kM4JdwUCWka8IgIbDAUJ A8JnAAAKCRCEf143kM4Jd9nXD/9jstJU6L1MLyr/ydKOnY48pSlZYgII9rSnFyLUHzNcW2c/ qw9LPMlDcK13tiVRQgKT4W+RvsET/tZCQcap2OF3Z6vd1naTur7oJvgvVM5lVhUia2O60kEZ XNlMLFwLSmGXhaAXNBySpzN2xStSLCtbK58r7Vf9QS0mR0PGU2v68Cb8fFWcYu2Yzn3RXf0Y dIVWvaQG9whxZq5MdJm5dknfTcCG+MtmbP/DnpQpjAlgVmDgMgYTBW1W9etU36YW0pTqEYuv 6cmRgSAKEDaYHhFLTR1+lLJkp5fFo3Sjm7XqmXzfSv9JGJGMKzoFOMBoLYv+VFnMoLX5UJAs 0JyFqFY2YxGyLd4J103NI/ocqQeU0TVvOZGVkENPSxIESnbxPghsEC0MWEbGsvqA8FwvU7Xf GhZPYzTRf7CndDnezEA69EhwpZXKs4CvxbXo5PDTv0OWzVaAWqq8s8aTMJWWAhvobFozJ63z afYHkuEjMo0Xps3o3uvKg7coooH521nNsv4ci+KeBq3mgMCRAy0g/Ef+Ql7mt900RCBHu4tk tOhPc3J1ep/e2WAJ4ngUqJhilzyCJnzVJ4cT79VK/uPtlfUCZdUz+jTC88TmP1p5wlucS31k Thy/CV4cqDFB8yzEujTSiRzd7neG3sH0vcxBd69uvSxLZPLGID840k0v5sftPA== Message-ID: <1f2ca124-bb7c-d02c-07cd-4afe6a634ee6@maciej.szmigiero.name> Date: Fri, 17 Aug 2018 19:27:17 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.0 MIME-Version: 1.0 In-Reply-To: <19c68f93-017d-cda1-632f-039ca3ca0158@kernel.dk> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16.08.2018 21:11, Jens Axboe wrote: > On 8/15/18 3:56 PM, Maciej S. Szmigiero wrote: >> The value that struct cftype .write() method returns is then directly >> returned to userspace as the value returned by write() syscall, so it >> should be the number of bytes actually written (or consumed) and not zero. >> >> Returning zero from write() syscall makes programs like /bin/echo or bash >> spin. > > Applied, thanks. Thanks. > Just a heads-up that gmail thinks your email is spam. Thanks for the information - it looks like gmail just doesn't like my email server for some reason. Maciej